Work

Selecting a sample size for studies with repeated measures

Year: 2013

Type: article

Abstract: Many researchers favor repeated measures designs because they allow the detection of within-person change over time and typically have higher statistical power than cross-sectional designs. However, the plethora of inputs needed for repeated measures designs can make sample size selection, a critical step in designing a successful study, difficult. Using a dental pain study as a driving example, we provide guidance for selecting an appropriate sample size for testing a time by treatment interaction for studies with repeated measures. We describe how to (1) gather the required inputs for the sample size calculation, (2) choose appropriate software to perform the calculation, and (3) address practical considerations such as missing data, multiple aims, and continuous covariates.

Source: BMC Medical Research Methodology

DOI: 10.1186/1471-2288-13-100

Authors: Yi Guo, Henrietta L Logan, Deborah H Glueck, Keith E Muller

Institutions: University of Florida, Colorado School of Public Health, University of Colorado Denver

Language: English

Topic: Statistical Methods in Clinical Trials

Subfield: Statistics and Probability

Field: Mathematics

Domain: Physical Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $3,090